Windows Vista (32-bit) would randomly freeze on my computer, usually 15-30 minutes after login but can happen just after login. All applications would stop responding and the hard drive will not make any sound, and after a while, the mouse cursor will also stop moving. I dual-boot Ubuntu, and that still works fine.

It started with the computer freezing when loading Team Fortress 2. Alt-Tab and Ctrl-Alt-Del have no effect, and the hard drive does not make any sound. I tried to verify the game data using Steam and that freezes the computer too. So I stupidly reinstalled the game. Now the game doesn't freeze when it starts, but instead the whole computer randomly freezes.

This computer is a Dell XPS M1530 with a 320GB (298GiB) drive (WDC WD3200BEVT-7) split 5-ways, with Windows and Linux a partition each, one more for Linux swap space, and another two partitions for Dell diagnostic program and factory image and drivers. There was once where the hard drive would make clicking noises all day, and only stopped when I rebooted the computer. Since then, the BIOS diagnostics would fail the drive (for "self-test log contains previous errors") whenever ran. (The on-disk diagnostics cannot be run because I overwrote the MBR with GRUB.) Naturally, I thought the hard drive could be the problem.

CHKDSK found one bad sector, but this seems to have no effect. System File Checker found two protected files with wrong hashes, one is some kind of IE manifest, and the other is a tcpmon.ini. Neither of them can be restored because their back up copy also have wrong hashes. Nothing about system failures in the event viewer.

What should I do next?